She's the drive-thru specialist who is celebrating 40 years working there, and she's by far one of the longest-tenured employees.
"It opened January of '79, I came in August of '79," she said.
DelRossi has sort of a formula to how she's kept the same job for decades.
"You keep treating customers good, and they'll come back to you," she said. "You give them good, awesome service, and they'll tell other people."
It's a trait not lost on her bosses.
"A customer came in with her car packed full and two little kids, and she said to me, 'You know we were leaving today to move across the country, just my kids wouldn't go until we got to say goodbye to Mary,'" franchise owner Laura Sander said.
Sander helped organize a party to honor DelRossi's 40 years, complete with cake, decorations and plenty of customers who wanted to sing her praises.
"We come here almost every day, and just from my voice, she knows what I want," one customer said.
"She serves people with a smile," said another.
"I just love my customers, and I'll say to them, 'Thank you, have a great day,' and just lift their spirits," DelRossi said.
After 40 years at the same job, a lot of people would be thinking about retiring or trying something new. But for Mary, she's not leaving this drive-thru anytime soon.
"Maybe 15, 20 more years," she said.
* Follow us on YouTube
* More local news
* Send us a news tip
* Download the abc7NY app for breaking news alerts